Hot-gas engine

ABSTRACT

A hot-gas engine constructed as rotary piston engine of trochoidal type which includes a piston supported on an eccentric of an eccentric shaft which together with a housing casing and with lateral housing parts arranged on both sides of the housing casing forms working chambers for the working medium; the eccentric space is thereby filled with the working medium under pressure while the ecentric shaft is sealed off on the outside of the bearing support by a labyrinth seal and a liquid seal.

llnited States Patent [191 Pattas et al.

[111 3,827,837 [451 Aug. 6, 1974 HOT-GAS ENGINE Inventors: Konstantin Pattas, Winterbach;

Hans-Peter Glathe, Neustadt, both of Germany Daimler-Benz Aktiengesellschaft, Stuttgart, Germany Filed: Nov. 27, 1972 Appl. No.: 309,922

Assignee:

Foreign Application Priority Data Nov. 27, 197] Germany 2158964 US. Cl. 418/104 Int. Cl. F0lc 19/00 Field of Search 277/56, 67, 135; 418/61 A,

References Cited UNITED STATES PATENTS 7/1971 Keylwcrt et al l23/8.0l

Primary Examiner-C. J. Husar Assistant Examiner-Leonard Smith Attorney, Agent, or Firm-Craig and Antonelli l 57 ABSTRACT A hot-gas engine constructed as rotary piston engine of trochoidal type which includes a piston supported on an eccentric of an eccentric shaft which together with a housing casing and with lateral housing parts arranged on both sides of the housing casing forms working chambers for the working medium; the eccentric space is thereby filled with the working medium under pressure while the ecentric shaft is sealed off on the outside of the bearing support by a labyrinth seal and a liquid seal.

12 Claims, 1 Drawing Figure PATENTEU 61974 1 HOT-GAS ENGINE The present invention relates to a hot-gas engineconstructed as a rotary piston engine of trochoidal construction, essentially consisting of-a piston which is rotatably supported on an eccentric of an eccentric shaft and which forms working chambers for the working medium together with a housing casing and with lateral parts arranged on both sides of the housing casing.

The hot-gas process of such engines takes place in a closed circulation between the expansion space and the compression space. it is known that the engines have an unfavorable efficiency by reason of their incomplete seal between the working chambers and last, but not least, between working chamber and eccentric space. It is the aim of the present invention to eliminate this drawback in an advantageous manner.

It is therefore proposed according to the present invention that the eccentric space of the rotary piston engine is filled with the working medium under pressure and the eccentric shaft is sealed off outside of the bearing support by a labyrinth seal and by a liquid seal.

The arrangement made in accordance with the present invention enables to nearly exclude leakage gas losses and thereby to considerably increase the power output.

In a preferred embodiment according to the present invention, the pressure prevailing in the eccentric space can lie between the minimum and the maximum pressure in the working space.

In an advantageous construction the labyrinth seal may be arranged according to the present invention in a closure part secured at the end face of the lateral part and may be in communication with the eccentric space by way of a channel disposed in the closure part and in the lateral part. Furthermore, a leakage fluid space may be arranged within the closure part downstream of the labyrinth seal, i.e., to the rear thereof which collects the leakage fluid that is fed back again the the liquid seal by way of a reservior. Leakage losses are avoided thereby.

According to a further feature of the present invention, the eccentric shaft includes a sleeve or bushing outside of the bearing support which rotates in unison with the eccentric shaft and which together with several closed rings disposed adjacent one another and arranged on the sleeve forms sealing gaps of invariable or non-changeable magnitude. The rings are stopped in the closure part by means of counter-parts which form the axial abutment.

According to the present invention, the liquid seal may consist of a lubricating oil with high viscosity.

Accordingly, it is an object of the present invention to provide a hot-gas engine in the form of a rotary piston engine of trochoidal construction which avoids by simple means the aforementioned shortcomings and drawbacks encountered in the prior art.

Another object of the present invention resides in a hot-gas engine constructed as rotary piston engine of trochoidal construction which is characterized by a higher degree of efficiency and is able to produce greater power outputs.

A further object of the present invention resides in a hot-gas engine of the type described above which makes it possible to exclude nearly completely all leakage gas losses.

These and other objects, features and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, one embodiment in accordance with the present invention, and wherein:

The single FIGURE is a partial cross-sectional view of one embodiment of a hot-gas engine in accordance with the present invention.

Referring now to the single FIGURE of the drawing, a rotary piston engine generally designated by reference numeral 1, of which a part is illustrated in longitudinal cross section, consists of an eccentric shaft 2 which is rotatably supported in a lateral housing part 4 by means of a roller bearing 3. A channel 6 starting from an eccentric space 5 is arranged in the lateral part 4, which channel terminates in a channel 9 disposed in the closure part 8 which is secured at the lateral part 4.

Piston l9 and housing casing 18, along with lateral parts 4, 4', delimit working chambers 20. Bearing 21 connects piston 19 with eccentric shaft 2.

A connection from the eccentric space S to the labyrinth seal is established by the two channels 6 and 9 connected with each other whereby a fluid 10, in this case, lubricating oil with high viscosity is arranged upstream of the labyrinth seal as a liquid seal.

A sleeve 11 is clampingly mounted on the eccentric shaft 2 outside of the bearing support for the latter; the sleeve 11 forms sealing gaps by means of several closed rings 12 which are disposed at uniform spacings separated from one another. The rings 12 engage with slight play in the recesses 13 of the counter-parts 14 secured in the closure part 8 and in this manner form together the labyrinth seal generally designated by reference numeral 7. Downstream or to the rear of the labyrinth seal 7 is disposed a leakage fluid space 17 delimited by a cover 15, which is threadably secured at the closure part 8, and by a seal 16 of conventional construction; the leakage fluid space 17 is under atmospheric pressure.

The eccentric space 5 is filled with a medium that corresponds to the working medium serving for the hot-gas process, for example, hydrogen or helium. Furthermore, this medium is in the eccentric space 5 and in the channels 6 and 9 under a pressure that lies between the minimum pressure and the maximum pressure of the working medium in the working chambers.

In order to be able to keep constant this high pressure in the eccentric space 5, lubricating oil is stored additionally within the channel 9 ahead of the labyrinth seal 7.

The labyrinth seal 7 is so dimensioned in its size that a pressure equalization exists between the channel 9, 6 and the eccentric space 5 and between the leakage fluid space 17 and the atmosphere disposed outside of the engine.

Leakage losses which eventually may occur are fed from the leakage fluid space 17 into a reservoir (not shown). From the latter, the lubricating oil is replenished, i.e., the liquid level of the lubricating oil is kept constant above the sealing gap at the labyrinth seal 7.

It is achieved by the construction of the rotary piston engine according to the present invention by means of the working medium which is accommodated in the eccentric space 5 and is under high pressure, that an optimum gas seal and therewith smallest leakage gas losses are assured between the working chambers among each other and between the working chambers and the eccentric space 5.

While we have shown and described only one embodiment in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to those skilled in the art, and we therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

What we claim is:

l. A hot-gas engine constructed as a rotary piston engine of trochoidal type, comprising:

a piston supported for eccentric rotation on an eccentric shaft,

a housing for said piston including a circumferentially extending housing casing means and lateral housing parts, said casing means and said piston delimiting a variable volume working chamber for accommodating working medium of said engine, one of said lateral housing parts and one of the lateral sides of said piston forming an eccentric space, and

bearing support means in said lateral housing parts for supporting said eccentric shaft,

wherein the eccentric space is filled with the working medium under pressure, and wherein the eccentric shaft is sealed along portions thereof outwardly of said bearing support means by a labyrinth seal means and by a liquid seal means.

2. A hot-gas engine according to claim 1, characterized in that the liquid seal means consists of a lubricating oil with high viscosity.

3. A hot-gas engine according to claim 1, characterized in that the labyrinth seal means is arranged at a closure part secured at an end face of a lateral part, and in that the closure part is in communication with the eccentric space by way of channel means disposed in the closure part and in the respective lateral part.

4. A hot-gas engine according to claim 3, characterized in that a leakage fluid space is arranged behind the labyrinth seal means within the closure part.

5. A hot-gas engine according to claim 1, characterized in that the eccentric shaft is provided outside the bearing support means with a sleeve means rotating in unison with the eccentric shaft, several closed rings disposed adjacent one another and arranged on the sleeve means forming sealing gaps of substantially nonchangeable magnitude.

6. A hot-gas engine according to claim 5, characterized in that counter means forming axial abutment means for the rings are secured in the closure part.

7. A hot-gas engine according to claim 1, characterized in that the pressure prevailing within the eccentric space lies between the minimum and maximum pressure in the working chamber.

8. A hot-gas engine according to claim 7, characterized in that the labyrinth seal means is arranged at a closure part secured at an end face of a lateral part, and in that the closure part is in communication with the eccentric space by way of channel means disposed in the closure part and in the respective lateral part.

9. A hot-gas engine according to claim 8, characterized in that a leakage fluid space is arranged behind the labyrinth seal means within the closure part.

10. A hot-gas engine according to claim 9, characterized in that the eccentric shaft is provided outside the bearing support means with a sleeve means rotating in unison with the eccentric shaft, several closed rings disposed adjacent one another and arranged on the sleeve means forming sealing gaps of substantially nonchangeable magnitude.

11. A hot-gas engine according to claim 10, characterized in that counter means forming axial abutment means for the rings are secured in the closure part.

12. A hot-gas engine according to claim 11, characterized in that the liquid seal means consists of a lubricating oil with high viscosity. 

1. A hot-gas engine constructed as a rotary piston engine of trochoidal type, comprising: a piston supported for eccentric rotation on an eccentric shaft, a housing for said piston including a circumferentially extending housing casing means and lateral housing parts, said casing means and said piston delimiting a variable volume working chamber for accommodating working medium of said engine, one of said lateral housing parts and one of the lateral sides of said piston forming an eccentric space, and bearing support means in said lateral housing parts for supporting said eccentric shaft, wherein the eccentric space is filled with the working medium under pressure, and wherein the eccentric shaft is sealed along portions thereof outwardly of said bearing support means by a labyrinth seal means and by a liquid seal means.
 2. A hot-gas engine according to claim 1, characterized in that the liquid seal means consists of a lubricating oil with high viscosity.
 3. A hot-gas engine according to claim 1, characterized in that the labyrinth seal means is arranged at a closure part secured at an end face of a lateral part, and in that the closure part is in communication with the eccentric space by way of channel means disposed in the closure part and in the respective lateral part.
 4. A hot-gas engine according to claim 3, characterized in that a leakage fluid space is arranged behind the labyrinth seal means within the closure part.
 5. A hot-gas engine according to claim 1, characterized in that the eccentric shaft is provided outside the bearing support means with a sleeve means rotating in unison with the eccentric shaft, several closed rings disposed adjacent one another and arranged on the sleeve means forming sealing gaps of substantially non-changeable magnitude.
 6. A hot-gas engine according to claim 5, characterized in that counter means forming axial abutment means for the rings are secured in the closure part.
 7. A hot-gas engine according to claim 1, characterized in that the pressure prevailing within the eccentric space lies between the minimum and maximum pressure in the working chamber.
 8. A hot-gas engine according to claim 7, characterized in that the labyrinth seal means is arranged at a closure part secured at an end face of a lateral part, and in that the closure part is in communication with the eccentric space by way of channel means disposed in the closure part and in the respective lateral part.
 9. A hot-gas engine according to claim 8, characterized in that a leakage fluid space is arranged behind the labyrinth seal means within the closure part.
 10. A hot-gas engine according to claim 9, characterized in that the eccentric shaft is provided outside the bearing support means with a sleeve means rotating in unison with the eccentric shaft, several closed rings disposed adjacent one another and arranged on the sleeve means forming sealing gaps of substantially non-changeable magnitude.
 11. A hot-gas engine according to claim 10, characterized in that counter means forming axial abutment means for the rings are secured in the closure part.
 12. A hot-gas engine according to claim 11, characterized in that the liquid seal means consists of a lubricating oil with high viscosity. 